1. Technical Field
This disclosure relates generally to instruments for measuring optical properties of materials.
2. Background Art
The evaluation of a material's optical characteristics can include testing some or all of transmittance, reflectance and absorbance for the material under various conditions. Transmittance is a measurement of the fraction of incident light (electromagnetic power) that passes through a material. Transmittance is a positive real number and is equal to a ratio of the power of light which is transmitted through a sample material to the power of light which is originally incident upon that sample material. The transmittance of a material layer can vary with a variety of factors such as light's angle of incidence, its wavelength, and its polarization. Thus, to fully characterize the transmittance of a material layer for a specific wavelength, transmittance measurements should be taken at a variety of different incident angles. Fully and accurately characterizing the transmittance of a material layer can be a time consuming process.